JPH0567912A - Flat antenna - Google Patents

Abstract

PURPOSE:To obtain a flat antenna compatible with two kinds of polarized waves having an excellent antenna characteristic and manufactured inexpensively in which electromagnetic coupling is enhanced between a feeding probe and an aperture. CONSTITUTION:Square apertures 6 are punched in a 2nd radiation circuit board 5. A feeding probe 7a corresponding to the apertures 6 of the radiation circuit board 5 is formed to a 2nd feeding circuit board 4. The feeding probe 7a is arranged opposite to the relevant apertures 6 so as to be in electromagnetic coupling. Slots 9, 9 corresponding to the apertures 6 in pairs are formed to a 1st radiation circuit board 3. A first power feeding circuit plate 2 is intersected orthogonally with the prolonged direction of the power feeding probe 7a of the power feeding circuit plate 4 and the power feeding probe 10a prolonged in a direction coupled electromagnetically with a pair of slots 9, 9 is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat antenna compatible with broadcasting satellites and communication satellites.

[0002]

2. Description of the Related Art At present, planar antennas are practically used for reception of broadcasting satellites. Conventional planar antennas for receiving broadcast satellites have been proposed that are formed by bending a strip line into a crank shape, or are configured by a plurality of patch elements.

However, these flat antennas generally have a narrow band, and it is difficult to have sufficient performance in the entire broadcasting band extending from 300 to 400 MHz. Therefore, a triplate type planar antenna consisting of a ground conductor plate, a feeding circuit plate, and a radiation circuit plate was developed for high efficiency and wide band, and it has reached the same level of reception performance as a parabolic antenna.

However, in order to support communication satellites,
It is essential to develop an antenna that supports two types of polarized waves, horizontal and vertical. Further, even in the case of a broadcasting satellite, it is considered to use two types of polarized waves of right-handed circular polarization and left-handed circular polarization when increasing the number of channels.

[0005]

However, the above-mentioned two types of polarized waves cannot be dealt with by the configuration of the conventional planar antenna. Therefore, as shown in U.S. Pat. No. 4,929,959, two types of feeding circuits are provided. A planar antenna formed by sequentially stacking a plate and a radiation circuit plate has been proposed, but there are problems such as an increase in cost and a large variation in performance as the number of circuits increases.

Particularly, in the case of two types of circularly polarized waves, the cross polarization characteristic is deteriorated and an interference problem occurs. The present invention has been made in view of the above-mentioned problems, and the object thereof is to be manufactured at low cost, and further, it has good antenna characteristics by strengthening electromagnetic coupling between the feeding probe and the aperture, Two types of linear polarization in the horizontal and vertical directions or two types of circular polarization of left-handed circular polarization and right-handed circular polarization with good cross-polarization characteristics and high efficiency over a wide band To provide a planar antenna corresponding to.

[0007]

In order to achieve the above-mentioned object, the invention according to claim 1 is a ground conductor plate, a first feeding circuit board, a first radiating circuit board, a second feeding circuit board, and a second feeding circuit board. 2 radiating circuit boards are laminated so that they are sequentially separated from each other by a dielectric,
Cross polarized waves are generated between the power supply circuit of the first power supply circuit board and the power supply circuit of the first radiation circuit board and the power supply circuit of the second power supply circuit board and the radiation circuit of the second power supply circuit board. In the planar antenna arranged as described above, the radiating element of the radiating circuit of the second radiating circuit board is formed by the aperture, and the slot corresponding to this aperture is formed as the radiating element of the radiating circuit of the first radiating circuit board. Then, the feeding probe guided from the feeding circuit of the first feeding circuit board is electromagnetically coupled to each pair of slots of the first radiating circuit board, and to each aperture of the second radiating circuit board. The power supply probe guided from the power supply circuit of the second power supply circuit board is electromagnetically coupled.

According to a second aspect of the present invention, in the first aspect of the present invention, a conductor element is arranged in the vicinity of the power supply probe guided from the power supply circuit of the second radiation circuit board without contacting the power supply probe. Is. According to a third aspect of the present invention, in the second aspect of the invention, a pair of rectangular conductor elements are provided on the same plane with respect to the power supply probe of the second power supply circuit board and on both sides thereof with a certain distance therebetween. is there.

According to a fourth aspect of the present invention, in the second aspect of the invention, a rectangular conductor element is provided on one side of the second feeding circuit board on the same plane and separated from the feeding probe by a certain distance. Is. According to a fifth aspect of the invention, in the second aspect of the invention, a pair of rectangular conductor elements are provided on the same plane with respect to the power supply probe of the second power supply circuit board and on both sides of the power supply probe, and both of them are separated by a certain distance. A conductor element is partially connected.

According to a sixth aspect of the present invention, in the first aspect of the invention, the first radiating circuit board and the second radiating circuit board are both made of a metal plate, and the respective slots and apertures are punched and formed. Is. According to a seventh aspect of the present invention, in the first aspect of the invention, the feeding probe of the second feeding circuit board, the slot of the first radiating circuit board, and the first radiating circuit board are provided in the projection of the aperture of the second radiating circuit board. The power supply probes are formed and arranged so that the power supply probes on the power supply circuit board are positioned.

According to an eighth aspect of the invention, in the first aspect of the invention, the size of the pair of slots of the first radiation circuit board is different. The invention according to claim 9 is
In the invention described in claim 1, a polarizer capable of converting linearly polarized waves into circularly polarized waves is installed above the second radiation circuit. According to a tenth aspect of the present invention, in the ninth aspect, the polarizer includes a sheet material having a foam material or a space portion and a printed circuit board on which a printed circuit board pattern is formed so as to have a polarization conversion function. It was done.

According to an eleventh aspect of the invention, in the invention according to the ninth aspect, the polarizer is formed by printing and forming a pattern having a polarization conversion function on a foam material or a sheet material having a space portion. Is. According to a twelfth aspect of the invention, in the invention according to the ninth aspect, a meander line is used as a pattern having a polarization conversion function of a polarizer.

[0013]

Thus, according to the present invention, the radiating element of the radiating circuit of the second radiating circuit board is formed by the aperture, and the slot corresponding to this aperture in a pair is formed in the radiating circuit of the first radiating circuit board. Each of the second radiating circuit boards is formed as a radiating element, and electromagnetically coupled to the pair of slots of the first radiating circuit board, the feeding probe guided from the feeding circuit of the first feeding circuit board. Since the feeding probe guided from the feeding circuit of the second feeding circuit board is electromagnetically coupled to the aperture, the cross polarization characteristic which is indispensable in the polarization receiving antenna in the two directions of the horizontal direction and the vertical direction is essential. Broadband has become possible.

In particular, a power supply probe of the second power supply circuit board,
If the electromagnetic coupling with the aperture of the second radiation circuit board is performed by the conductor element installed near the feeding probe, the coupling can be improved. Further, since the aperture is formed in the first radiating circuit board and the slot is formed in the second radiating circuit board to form the respective radiating elements, the metal plate punching process which is easy to manufacture and can be manufactured at low cost is performed. It can be used for manufacturing radiating circuit boards.

Further, if both the first radiating circuit board and the second radiating circuit board are made of metal plates and the respective slots and apertures are formed by punching, the radiating circuit board is made rigid and the ground conductor and the feeding circuit board are provided. It is possible to improve the accuracy of the distance between the radiating circuit boards and minimize the variation in antenna performance.
If a polarizer that can convert linearly polarized waves to circularly polarized waves is installed above the second radiation circuit, two types of linearly polarized waves can be converted into two types of circularly polarized waves, right and left circularly polarized waves. In addition, good cross polarization characteristics and high efficiency can be achieved over a wide band.

[0016]

EXAMPLES The present invention will be described below with reference to examples. (Embodiment 1) In this embodiment, as shown in an exploded perspective view of which a part is omitted in FIG. 1 and a sectional view of which a part is omitted in FIG. 2, a ground conductor plate 1, a first feeding circuit board 2 and a first radiation are shown. The circuit board 3, the second feeding circuit board 4, and the second radiating circuit board 5 are sequentially laminated so as to be separated from each other by a dielectric 11 made of a foamed plastic sheet.

The second radiation circuit board 5 is made of a metal plate such as aluminum having a thickness of 0.4 mm, and square apertures 6 each having a side of 16 mm are punched into 16 rows and 16 columns with a pitch between centers of 23 mm. It was formed. The second power supply circuit board 4 arranged below the radiation circuit board 5 at a constant interval (for example, 1 mm) is composed of a flexible board in which a copper foil is laminated on a polyester board having a thickness of 50 μm. A power supply probe 7a corresponding to each aperture 6 and a crank-shaped circuit connecting these power supply probes 7a are formed by etching.

The feed probe 7a has a corresponding aperture 6
On the other hand, as shown in FIG. 3, it is positioned so that it can be electromagnetically coupled. The second radiating circuit board 3 arranged below the power feeding circuit board 4 with a constant space (for example, 1 mm).
Is made of a metal plate such as aluminum having a thickness of 0.4 mm, and is punched out in 32 rows and 16 columns so that a pair of slots 9 each having a rectangular shape with a long side of 15 mm and a short side of 2 mm correspond to each aperture 6. It is formed by processing.

The first power supply circuit board 2 arranged below the radiation circuit board 3 with a constant space (for example, 2 mm) is 5
It is made of a flexible substrate in which a copper foil is laminated on a polyester substrate having a thickness of 0 μm, and can be electromagnetically coupled to each pair of slots 9 and 9 of the radiation circuit board 3, and the extension of the feeding probe 7a of the feeding circuit board 4. A feeding circuit is configured by forming a feeding probe 10a extending in a direction orthogonal to the direction and a circuit connecting the feeding probe 10a by etching processing.

The ground conductor 1 arranged below the power supply circuit board 4 with a constant space (for example, 2 mm) is made of a metal plate such as aluminum having a thickness of 2 mm and which is commercially available.
Then, as shown in FIG. 3, in the projection of the aperture 6 of the radiation circuit board 5, the feeding probe 7a of the feeding circuit board 4, the pair of slots 9 and 9 of the radiation circuit board 3, and the feeding probe 7a.
The circuit boards 5, 4, 3 and 2 and the ground conductor plate 1 are sequentially laminated so that the power supply probes 10a of the power supply circuit board 2 orthogonal to each other face each other, and the dielectric 11 made of a foamed plastic sheet is interposed between the circuit boards 5, 4, 3, 2. A planar antenna is formed by interposing it. Of course, a space layer made of air may be used as the dielectric 11.

It can be confirmed that the planar antenna of Example 1 obtained by the above-described configuration can efficiently receive two types of linearly polarized waves in the horizontal direction and the vertical direction. Measurement of polarization characteristics 1
Over a wide band (1 GHz) of 1.2 to 12.2 GHz,
An efficiency of 64% or more and a cross polarization characteristic of 25 dB or more were obtained.

(Embodiment 2) FIG. 4 is an exploded perspective view of this embodiment, and this embodiment is basically the embodiment 1 as shown.
However, the pitch between the centers of the apertures 6 formed in the second radiation circuit board 5 is set to 20 mm. In addition, the second placed below the radiation circuit board 5
In addition to the power supply probes 7a corresponding to the apertures 6 of the radiation circuit board 5 and the crank-shaped circuit connecting these power supply probes 7a, each power supply circuit board 4 is sandwiched by both side pieces as shown in FIG. As described above, the feeding circuit is configured by additionally forming the concave conductor element (parasitic element) 8 by etching.

The feeding probe 7a and the conductor element 8 are positioned so as to be electromagnetically coupled to the corresponding aperture 6, and the conductor element 8 has a function of enhancing electromagnetic coupling between the feeding probe 7a and the aperture 6. To do. The conductor element 8 has a long side length of 9 mm and a short side length of 5 mm. Further, the slot 9 of the second radiation circuit board 3 arranged below the power feeding circuit board 4 is formed in a rectangular shape having a long side of 9 mm and a short side of 2 mm.

Specifications other than the above are in accordance with the embodiment. Thus, as shown in FIG. 6, in the projection of the aperture 6 of the radiating circuit board 5, the feeding probe 7a and the conductor element 8 of the feeding circuit board 4 are provided.
And a pair of slots 9 and 9 of the radiation circuit board 3 and the feeding probe 1 of the feeding circuit board 2 orthogonal to the feeding probe 7a.
The circuit board 5, 4, 3, 2 and the ground conductor plate 1 are sequentially laminated so that the surface 0a faces, and a dielectric 11 made of a foamed plastic sheet is interposed between the circuit boards 5, 4, 3 and 2 and the ground conductor plate 1, and the planar antenna is arranged between them. To form. Of course, a space layer made of air may be used as the dielectric 11.

It can be confirmed that the planar antenna of the second embodiment obtained as configured above can efficiently receive two types of linearly polarized waves in the horizontal direction and the vertical direction. Measurement of polarization characteristics 1
Over a wide band (1 GHz) of 1.2 to 12.2 GHz,
An efficiency of 64% or more and a cross polarization characteristic of 25 dB or more were obtained.

Although the conductor element 8 and the feeding probe 7a are formed on the same surface of the same substrate in this embodiment, the same effect as described above can be obtained by forming them on both surfaces of the substrate. In other words, if the difference is about the thickness of the substrates, they can be regarded as the same plane. (Embodiment 3) The shape of the conductor element 8 in Embodiment 2 is the feeding probe 7a.
In the present embodiment, a pair of conductor elements (rectangles having a long side of 9 mm and a short side of 2 mm) 8a, 8 are arranged 0.5 mm apart on both sides of the feeding probe 7a as shown in FIG.
b is arranged.

In this example, the same characteristics as in Example 2 were obtained. (Fourth Embodiment) The conductor element in the third embodiment is arranged so as to sandwich the pair of conductor elements 8a and 8b arranged on both sides of the feeding probe 7a, but in the present embodiment, as shown in FIG.
0.5mm to one side (right side) of the conductor element (long side 9
mm, rectangular with a short side of 2 mm) 8a.

In this example, the same characteristics as in Example 1 were obtained. (Example 5) Although the pair of slots 9 which are the radiating elements of the first radiating circuit board 3 in the above-mentioned Examples 1 to 4 have the same size as shown in Figs. 1 and 4, this Example Then, as shown in FIG. 9, the size of one side 9a is about twice as large as that of one side 9b.

In this example, the same characteristics as those of Examples 1 to 4 were obtained. (Embodiment 6) The above-mentioned Embodiments 1 to 5 are flat antennas for receiving two types of linearly polarized waves, but in this embodiment, as shown in FIG. 10, a straight line is provided on the upper part of the second radiating circuit board 5. A polarizer 12 for converting a polarized wave into a circularly polarized wave is arranged.
Reference numeral 2 denotes a structure in which three flexible printed boards on which a pattern P consisting of so-called meander lines is formed by etching are installed above, inside, and below two foam boards.

Thus, the planar antenna of the present embodiment obtained by the above-described configuration has two types of circular polarization, that is, two linear polarizations, horizontal polarization and vertical polarization, which are right-hand circular polarization and left-hand circular polarization. It can be converted into a wave and can be efficiently received. When each VSWR, gain, and cross polarization characteristics are measured, it is 11.5-12.2.
An efficiency of 64% or more and a cross polarization characteristic of 25 dB or more were obtained over a wide band (0.7 GHz) of GHz.

In this embodiment, the basic structure is similar to that of the first embodiment, but it goes without saying that the structures of the second to fifth embodiments may be used as the basic structure. Further, in the above-described embodiment, the foam board is used as the base material of the polarizer 6 used, but a sheet material or a foam sheet having a space portion having a similar dielectric constant may be used, or the pattern may be directly foamed. Of course, a sheet may be formed by printing, or a pattern may be formed on a printed circuit board as in the first embodiment, and instead of the foam board, a base material in which a sheet material having a space portion having a similar dielectric constant is combined may be used. ..

In the first to sixth embodiments, metal plates such as aluminum are used for the first and second radiating circuit boards 3 and 5, and the slot 9 and the aperture 6 are formed by punching. It may be formed by etching using the copper foil portion of the flexible printed circuit board as a conductive plate. Also in this case, the antenna characteristics similar to those in Examples 1 to 6 were obtained.

[0033]

According to the first aspect of the present invention, the radiating element of the radiating circuit of the second radiating circuit board is formed by an aperture, and a slot corresponding to the aperture in a pair is provided in the radiating circuit of the first radiating circuit board. Of the second radiating circuit board by electromagnetically coupling the feeding probe guided from the feeding circuit of the first feeding circuit board to each pair of slots of the first radiating circuit board. Since the feeding probe guided from the feeding circuit of the second feeding circuit board is electromagnetically coupled to each aperture, the cross polarization characteristics that are essential for the horizontal and vertical polarization receiving antennas. There is an effect that it becomes possible to widen the band.

In particular, the invention according to claim 2 performs electromagnetic coupling between the feeding probe of the second feeding circuit board and the aperture of the second radiating circuit board by the conductor element installed in the vicinity of the feeding probe. The effect is that the coupling can be improved. Further, in the invention according to claim 6, since the aperture is formed in the first radiating circuit board and the slot is formed in the second radiating circuit board to form the respective radiating elements, the manufacturing is easy and can be manufactured at low cost. There is an effect that punching of a metal plate can be adopted for manufacturing these radiation circuit boards.

According to the invention of claim 7, the first radiating circuit board and the second radiating circuit board are both made of a metal plate, and the respective slots and apertures are formed by punching, so that the radiating circuit board is made rigid. It is possible to improve the accuracy of the space between the ground conductor, the feeding circuit board, and the radiation circuit board, and it is possible to minimize variations in antenna performance. According to the invention of claim 9, a polarizer capable of converting a linearly polarized wave into a circularly polarized wave is installed above the second radiating circuit. There is an effect that it can be converted into various types of circularly polarized waves, and that good cross polarization characteristics can be obtained over a wide band and the efficiency is also high.

In particular, the inventions of claims 10 to 12 can be achieved at a low cost because the pattern of the polarizer is formed by printing on the surface of the foam material or the sheet material, or the pattern is formed on the printed board by etching. There is an effect.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a first embodiment of the present invention with a part thereof omitted.

FIG. 2 is a sectional view in which a part of the first embodiment of the present invention is omitted.

FIG. 3 is a top view of an essential part of the first radiating circuit board, in which the first embodiment of the present invention is partially omitted.

FIG. 4 is an exploded perspective view of a second embodiment of the present invention with a part thereof omitted.

FIG. 5 is a top view of an essential part of the first radiation circuit board according to the first embodiment of the present invention with a part thereof omitted.

FIG. 6 is a positional relation explanatory view of Embodiment 2 of the present invention.

FIG. 7 is a top view of essential parts of a first radiating circuit board according to a third embodiment of the present invention, with a part thereof omitted.

FIG. 8 is a top view of essential parts of a first radiating circuit board according to a fourth embodiment of the present invention, with a part thereof omitted.

FIG. 9 is a top view of an essential part of a second radiating circuit board according to a fifth embodiment of the present invention, in which a part is omitted.

FIG. 10 is an exploded perspective view of the first embodiment of the present invention with a part thereof omitted.

[Explanation of symbols]

 1 Ground Conductor Plate 2 1st Feeding Circuit Board 3 1st Radiating Circuit Board 4 2nd Feeding Circuit Board 5 2nd Radiating Circuit Board 6 Aperture 7a Feeding Probe 9 Slot 10a Feeding Probe

Claims (12)

[Claims] 1. A ground conductor plate, a first feeding circuit plate, a first radiating circuit plate, a second feeding circuit plate, and a second radiating circuit plate are sequentially laminated so as to be separated from each other by a dielectric, The first feeder circuit board and the first radiator circuit board radiation circuit are
In the planar antenna arranged to generate cross polarization with respect to the feeding circuit of the feeding circuit board and the radiating circuit of the second radiating circuit board, the radiating element of the radiating circuit of the second radiating circuit board is formed by an aperture. In addition, a pair of slots corresponding to this aperture are formed as the radiating elements of the radiating circuit of the first radiating circuit board, and the power feeding of the first feeding circuit board is performed for each pair of slots of the first radiating circuit board. The power supply probe guided from the circuit is electromagnetically coupled, and the power supply probe guided from the power supply circuit of the second power supply circuit board is electromagnetically coupled to each aperture of the second radiation circuit board. And a planar antenna. 2. The plane antenna according to claim 1, wherein a conductor element is arranged in the vicinity of the feeding probe guided from the feeding circuit of the second radiating circuit board without contacting the feeding probe. 3. The planar antenna according to claim 2, wherein a pair of rectangular conductor elements are provided on the same plane with respect to the feeding probe of the second feeding circuit board and on both sides of the feeding probe with a certain distance therebetween. 4. The planar antenna according to claim 2, wherein rectangular feeding elements are provided on one side of the feeding probe of the second feeding circuit board on the same plane with a certain distance therebetween. 5. A pair of rectangular conductor elements are provided on the same plane and on both sides of the feed probe of the second feed circuit board at fixed intervals, and both conductor elements are partially connected. The planar antenna according to claim 2. 6. The planar antenna according to claim 1, wherein both the first radiating circuit board and the second radiating circuit board are made of a metal plate, and the respective slots and apertures are formed by punching. 7. The feeding probe of the second feeding circuit board, the slot of the first feeding circuit board, and the feeding probe of the first feeding circuit board are located in the projection of the aperture of the second radiation circuit board. The planar antenna according to claim 1, wherein each of them is formed and arranged. 8. The planar antenna according to claim 1, wherein the size of the pair of slots of the first radiating circuit board is different. 9. The planar antenna according to claim 1, further comprising a polarizer capable of converting a linearly polarized wave to a circularly polarized wave, which is installed above the second radiating circuit. 10. The plane according to claim 9, wherein the polarizer comprises a sheet material having a foam material or a space portion and a printed circuit board on which a printed circuit board pattern is formed so as to have a polarization conversion function. antenna. 11. The planar antenna according to claim 9, wherein the polarizer is formed by printing a pattern having a polarization conversion function on a foam material or a sheet material having a space portion. 12. The planar antenna according to claim 9, wherein a meander line is used as a pattern having a polarization conversion function of the polarizer.